According to the company, the BlackHole RAT release is still under development, and appears to be using the source code of a popular Windows trojan horse known as darkComet.

The screen lock feature reads:

Hello I'm the BlackHole Remote Administration Tool. I'm a trojan horse, so I have infected your Mac Computer. I know, most people think that Macs can't be infected, but look, you ARE infected! I have full controll over your Computer and I can do everything I want, and you can do nothing to prevent it. So, Im a very new virus, under Development, so there will be much more functions when I'm finished. But for now, it's okay what I can do. To show you what I can do, I will reboot your Computer after you have clicked the Button right down.

Open source malware is an inseparable part of the cybercrime ecosystem, allowing novice cybercriminals to quickly catch up with that used to be sophisticated propagation tactics, a few years ago.

With open source malware now every day's reality, it shouldn't be surprising the the growth of malware is reaching such epic proportions of the overall picture. Although rate, malware releases for Mac OS X are only going to get more popular with the time, given the under served market segment, combined with the countless number of malware coders.